School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, PR China.
School of Environmental Science and Engineering, Tianjin University/Tianjin Key Lab of Biomass/Wastes Utilization, Tianjin 300072, PR China.
J Hazard Mater. 2020 Jun 5;391:122218. doi: 10.1016/j.jhazmat.2020.122218. Epub 2020 Feb 2.
This paper conducted catalytic ozonation of CB (chlorobenzene) over a series of MnO based catalysts with different supports (AlO, TiO, SiO, CeO, and ZrO) at 120 °C. Mn/AlO exhibited highest CB conversion efficiency, ca. 82.92 %, due to its excellent textual properties, O desorption, redox ability, and desirable surface adsorbed oxygen species and acidity. O conversion all approached nearly 100.0%, with residual <10 ppm. Mn/AlO was further employed to investigate effect of temperature, O/CB, and space velocity on CB conversion. Hereafter, catalytic ozonation of single and binary VOCs in different types was performed, i.e., CB, DCE (dichloroethane), DCM (dichloromethane), and PhH (Benzene). Conversion results demonstrated aromatics degraded easier than alkanes and more carbon atoms decreased difficulty, as CB∼PhH > DCE∼DCM, and DCE > DCM; but chlorinated substitution increased difficulty, as PhH > CB. Catalytic co-ozonation of CB/DCE indicated that DCE significantly improved CB conversion to reach totally degradation at low O input, but inhibited DCE conversion, especially at higher ratio of DCE/CB. Co-ozonation improved ozone utilization efficiency, and maintained the original property of catalyst. By contrast, CB/PhH co-ozonation displayed very mild effects. Finally, critical intermediates during catalytic CB ozonation, i.e., DCM, carboxyl and formic acid, were detected from mass spectrum results.
本文在 120°C 下，用一系列不同载体（AlO、TiO、SiO、CeO 和 ZrO）的 MnO 基催化剂对 CB（氯苯）进行了催化臭氧化。由于 Mn/AlO 具有优异的织构性质、O 脱附、氧化还原能力以及理想的表面吸附氧物种和酸度，其 CB 转化率最高，约为 82.92%。O 的转化率均接近 100.0%，残留量<10ppm。进一步用 Mn/AlO 考察了温度、O/CB 和空速对 CB 转化率的影响。此后，在不同类型的单一组分和双一组分 VOCs 中进行了催化臭氧化，即 CB、DCE（二氯乙烷）、DCM（二氯甲烷）和 PhH（苯）。转化率结果表明，芳烃比烷烃更容易降解，碳原子越多难度越大，如 CB∼PhH > DCE∼DCM，DCE > DCM；但氯取代增加了难度，如 PhH > CB。CB/DCE 的催化共臭氧化表明，DCE 显著提高了 CB 的转化率，在低 O 输入下可达到完全降解，但抑制了 DCE 的转化率，特别是在较高的 DCE/CB 比下。共臭氧化提高了臭氧利用效率，并保持了催化剂的原有性质。相比之下，CB/PhH 共臭氧化的效果非常温和。最后，从质谱结果中检测到了催化 CB 臭氧化过程中的关键中间产物，即 DCM、羧基和甲酸。
